LONDON-British businesses are generally uninsured for the huge economic losses they have suffered as a result of terrorist attacks during the weeks running up to the May 1 general election.

A string of bombings and false bomb threats placed by the Irish Republican Army over the past two months have shut down roads, railways and airports, in a strategy designed to cause economic loss rather than bodily injury. Estimates have put the cost to British business at more than (British pounds) 100 million ($160 million).

In the most recent string of threats last week, London was brought nearly to a complete halt. Coded warnings, received by shops and hospitals shortly before 7 a.m. Monday, resulted in seven rail stations and the four London airports being closed for hours. No bombs were found, but the British Transport Police took the precaution of closing all the threatened buildings and evacuating the areas.

Gatwick Airport, one of the busiest London airports, was closed for most of the day. About 8,000 would-be travelers found themselves camped out on the tarmac as the terminals were evacuated and passengers on arriving planes were kept on board until the security alert was over.

A spokeswoman for Virgin Atlantic Airways Ltd. said that only one VAA flight-to Athens-was canceled, and she anticipated the loss to the airline to be minimal. Although a number of planes were delayed, they eventually took off for their original destinations, she said.

British Airways P.L.C., the largest airline in the United Kingdom, also sustained delays, incurring losses that will not be insured. A spokesman said the costs of the problems had not been fully assessed. "But the work we did during that day and overnight meant we were perfectly able to operate the timetable the following day."

Rail stations at Gatwick, Watford Junction, Kings Cross, St. Pancras, Charing Cross, Baker Street and Paddington were all closed, seriously delaying commuters both in and out of London. Most were reopened mid-morning, though Gatwick-which serves the airport-was closed until the middle of the afternoon.

A spokesman for the British Retail Assn., a trade association for retail outfits, said the economic loss was hard to judge because people would have bought any items they wanted from another store or at another time.

But previous bombs and threats may well have hurt retailers' bottom-line figures, said a spokesman for the Freight Transport Assn., a trade association representing all kinds of cargo transportation companies. On April 18, threats of devices beside motorways in the heart of England effectively cut off the north of the country from the south. This could well have delayed deliveries to supermarkets and other stores, and "if it's not on the shelves, people can't buy it," he pointed out.

The FTA estimated the basic economic loss to haulage companies of bombs placed on the same roads in March to be about (British pounds) 2.3 million ($3.7 million) each hour. Overall, the spokesman estimated the March delays to have cost his association's members about (British pounds) 10 million ($16.2 million), though he said this estimate was conservative and covered just the cost of the drivers' pay, fuel, road tax and insurance. Related costs, such as penalty payments for late deliveries, were not factored into the amount, he said.

Any businesses carrying terrorism insurance, whether through the U.K. government-backed reinsurer Pool Reinsurance Co. Ltd. or the various Lloyd's syndicates prepared to write the business, will not be able to claim for delays because of the disruption.

Currently, terrorism policies only cover for losses caused by physical damage to the insured's property or business interruption losses due to that physical damage. In addition, Pool Re coverage is triggered only after the first (British pounds) 100,000 ($162,000) on any claim. Leslie Lucas, chief executive of Pool Re, thought it unlikely that the reinsurer will see any claims, both because of the deductible and because in most cases there was no property damage. "The threat of a device. . .won't trigger a reinsurance claim to Pool Re," he said.

Raymond Dumas, underwriter at Wellington Underwriting P.L.C., said his syndicate will not see claims. "An essential of the policy is that there must be damage at the insured location," he explained.

"Mere threat is not an insurable loss, and mere delay is not an insurable loss," he said, adding that he would consider writing such business should he receive a request. "The Lloyd's marketplace has a tradition and pride that it would consider any risk," said Mr. Dumas.

Ina Barker, executive director of the Assn. of Insurance & Risk Managers, said new forms of terrorism coverage could be a "marvelous opportunity" for the insurance market. But she foresaw problems with assessing the risk exposures, for example putting a value on a proportion of a company's employees not being able to get to their workplace, or the business interruption and contingency costs of evacuating a factory. "Nevertheless, it is a risk which could be assessed," she said. "If it was put in as part of a business interruption program, I would have thought it would be of interest," she added.

In the meantime, AIRMIC is advising its members to remain vigilant, as it has since the start of the latest wave of IRA activity with last February's attack on London's Docklands area (BI, Feb. 19, 1996). Risk managers should ensure facilities such as closed circuit television cameras are used to monitor people in and out of their sites and that security is as tight as possible. What's more, they need a contingency plan that is constantly evolving alongside the organization and includes media relations. Such plans "have to be tested in real time," advised Ms. Barker.